PSSG Minimum Recommendations for Imaging/PFTs
for Patients Undergoing Treatment for Early Onset Scoliosis

General

• Standing x-ray preferred over sitting preferred over supine films
• Obtain lateral x-rays at initial presentation and then periodically thereafter
• Minimize patient radiation exposure

• Biplanar slot scanning microdose (EOS) preferred over traditional x-ray
• PA preferable to AP radiographs
• Digital preferable to radiographic films

Standardized Positioning

Standing

Sitting

Consider use of standardized radiolucent imaging chair

Casting

Precasting

• Standing (supine preferred if unable to stand) PA x-ray prior to initiation of casting
• Screening Cervical, Thoracic, Lumbar MRI at initiation of casting (see protocol below) - Consideration should be given to obtaining MRI during an initial or early subsequent casting procedure for all patients undergoing serial casting for IIS.
• Supine x-ray in first cast to confirm appropriate correction

Subsequent x-rays

• X-ray in cast every 12 months or at transition point
• Standing PA and lateral scoliosis x-ray out of device annually

Bracing

• Prior to bracing, obtain standing (supine or sitting if unable to stand) PA/AP and lateral x-ray
• Consider left hand bone age for age > 10 years prior to brace initiation

• X-ray in new brace (supine for night-time brace, standing for day-time brace)
• PA +/- lateral x-ray out of brace once or twice yearly. The general-sub should be instructed to be OOB 24 hours prior to appointment for EOS patients managed with bracing.

Nonfusion (Apifix and Vertebral Body Tethering)

• Standing preop PA and lateral scoliosis images
• Left hand bone age within 3 months prior to surgery
• Preoperative bending films (Standing left and right lateral bending films in EOS, supine left and right lateral bending, and/or thoracic fulcrum bend)
• PFTs: Preoperative, 6- month, 1-year, 2-year
• Scoliometer: Preoperative, 6-month, 1-year, 2-year thoracic and lumbar
• PA and lateral x-rays at 6 months, 1-year, 2-years, annually until skeletal maturity

Growing Rods

Growing Rods include Traditional Growing Rods, MCGR, VEPTR, and Shilla.

• Standing (or sitting) preop PA and lateral scoliosis images
• Preoperative flexibility radiograph
• PFTs: Preoperative, 6- month, 1-year, 2-year
• PA and lateral x-rays at 6 months, 1-year, 2-years, and annually until skeletal maturity

Pulmonary Function

Start PFT testing at age 5 years (assuming physical and cognitive ability) and ideally repeat yearly, if no symptoms and more frequently if symptomatic.

PFTs include FVC and FEV1, armspan, height, and weight

Minimum Suggestions:

• Preoperative PFTs prior to growing rod implant or growth modulation surgery
• 6-month, 1-year, 2-year and final fusion/skeletal maturity/STOP point
• Additional assessments: sleep studies, invasive assessments caveated by respiratory team requests
• Formal lab PFT evaluation preferred unless certified for POC spirometry

Axial Imaging/Navigation

MRI

Indications for screening (or extended screening) MRI:

• All patients under 10 years with significant curves
• Rapid progression
• Back pain, significant headaches
• Abnormal neurologic findings
• All patients with congenital scoliosis or congenital kyphosis with progressive deformity (consider renal ultrasound and cardiac echocardiogram in patients with new diagnosis of congenital scoliosis)
• Patients scheduled for surgery
• Consideration should be given to obtaining MRI during an initial or early subsequent casting procedure for all patients undergoing serial casting for IIS

Recommended sequences:

• Screening: sagittal T1; sagittal T2
• Extended screening: sagittal T1; sagittal T2; axial T2 (over apex); coronal T1 vibe (over apex) and sagittal T1 vibe (lumbosacral)
• Full MRI: sagittal T1, sagittal T2, axial T1, axial T2, coronal T2, FSE / STIR sequences

CT

• Preoperative CT should be limited to the zone/anatomy of interest and surgeons should communicate the exact levels desired to be imaged to radiology team
• Obtain CT only as needed for aberrant anatomy (revision surgery, congenital scoliosis) or surgical planning/navigation
• If possible, routine CT for congenital scoliosis should be delayed until surgical intervention is needed
• CTs should be obtained at lowest reasonable dose
• Intraoperative low dose protocols for cone beam CT/intraop CT should be utilized when possible (for instance, 80 kV/20 mA/ 80 mAs for patients > 60 kgs)

Observation

Observation is often recommended for children with early onset scoliosis. For young infants with no congenital malformations there is up to 80-90% resolution of scoliosis. It is still worthwhile to refer to a pediatric spine specialist, because there are certain radiographic and clinical features in infants that indicate high risk of progression. These children often can be successfully treated with serial spine casting.

Children with congenital scoliosis also are often observed when they are young. The risk of progression and rate of progression will vary based on type of congenital scoliosis. Referral to a pediatric spine surgeon is advised, as children will require unique care based on their individual deformity.

Other varieties of early onset scoliosis also may be managed with observation initially even if surgery is anticipated. This generally is done to allow for additional longitudinal growth and pulmonary development as long as possible prior to attempting to alter the natural history with casting or surgery.

References

• Murgai RR, Tamrazi B, Illingworth KD, Skaggs DL, Andras LM. Limited Sequence MRIs for Early Onset Scoliosis Patients Detected 100% of Neural Axis Abnormalities While Reducing MRI Time by 68. Spine (Phila Pa 1976). 2019 Jun 15;44(12):866-871. doi: 10.1097/BRS.0000000000002966. PMID: 30540716.
• Su AW, McIntosh AL, Schueler BA, Milbrandt TA, Winkler JA, Stans AA, Larson AN. How Does Patient Radiation Exposure Compare With Low-dose O-arm Versus Fluoroscopy for Pedicle Screw Placement in Idiopathic Scoliosis? J PediatrOrthop. 2015. doi: 10.1097/BPO.0000000000000608. PubMed PMID: 27453221.
• Sarwahi V, Payares M, Wendolowski S, Maguire K, Thornhill B, Lo Y, Amaral TD. Low-Dose Radiation 3D Intraoperative Imaging: How Low Can We Go? An O-Arm, CT Scan, Cadaveric Study. Spine (Phila Pa 1976). 2017;42(22):E1311-E7. doi: 10.1097/BRS.0000000000002154. PubMed PMID: 28296816.
• Abul-Kasim K, Soderberg M, Selariu E, Gunnarsson M, Kherad M, Ohlin A. Optimization of radiation exposure and image quality of the cone-beam O-arm intraoperative imaging system in spinal surgery. Journal of spinal disorders & techniques. 2012;25(1):52-8. Epub 2011/03/23. doi: 10.1097/BSD.0b013e318211fdea. PubMed PMID: 21423057.
• Su AW, Luo TD, McIntosh AL, Schueler BA, Winkler JA, Stans AA, Larson AN. Switching to a Pediatric Dose O-Arm Protocol in Spine Surgery Significantly Reduced Patient Radiation Exposure. J PediatrOrthop. 2016;36(6):621-6. doi: 10.1097/BPO.0000000000000504. PubMed PMID: 26296221.